Bioefficacy of Biopesticides and Chemical Insecticides against Wheat Aphid. (Rhopalosiphum padi L.)

Wheat aphid (Rhopalosiphum padi L.) is an important insect pest of wheat, affecting crop growth, grain formation and yield. Effective management of aphid infestations is essential for sustaining wheat productivity. However, comparative information on the efficacy of biopesticides and chemical insecticides under local field conditions remains limited, highlighting the need to evaluate their effectiveness against wheat aphids and their influence on grain yield. A field experiment was conducted during rabi, 2025–26 at the research farm of Krishi Vigyan Kendra, Dhule, to evaluate the bioefficacy of biopesticides and chemical insecticides against wheat aphid (Rhopalosiphum padi L.) on wheat. Eight treatments, namely Lecannicillium lecanni 1.15% WP, Metarhizium anisopliae 1.15% WP, Azadirachtin 10000 ppm, Clothianidin 50 WDG, Thiamethoxam 25 WG, Imidacloprid 17.8 SL, NSKE 5%, and an untreated control, were evaluated in a randomised block design with three replications. Based on the mean of two sprays, Thiamethoxam 25 WG @ 50 g/ha proved to be the most effective treatment against wheat aphid, recording the lowest aphid population of 0.00, 0.00, and 2.57 aphids per shoot per plant at 3, 7, and 14 days after spraying (DAS), respectively. It was followed by Clothianidin 50 WDG @ 60 g/ha, which recorded 0.00, 0.00, and 4.27 aphids per shoot per plant at the respective observation intervals. Among the biopesticides, Metarhizium anisopliae 1.15% WP @ 2.50 kg/ha was the most effective, recording 11.13, 3.70, and 6.97 aphids per shoot per plant at 3, 7, and 14 DAS, respectively, followed by Azadirachtin 10000 ppm @ 1.5 L/ha, which recorded 12.00, 5.63, and 9.77 aphids per shoot per plant. Treatment with Thiamethoxam 25 WG recorded the highest grain yield (45.96 q/ha). This represented an additional yield of 16.50 q/ha compared with the untreated control.